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The juvenile ECG pattern in adolescent athletes and non-athletes in a national cardiac screening program (BEAT-IT)
Mark Abela1, Kentaro Yamagata2, Lisa Buttigieg2
1Department of Cardiology, Mater Dei Hospital, Tal-Qroqq, Malta; Medical School, University of Malta, Malta; St. George's, University of London, London, United Kingdom.
Background:
Anterior T wave inversion (TWI) is frequent in healthy adolescent individuals (juvenile ECG pattern), normalising after puberty. Its clinical implications are uncertain.
Aim:
This study assessed a) national prevalence of anterior TWI, b) ST segment morphology, c) proportion of individuals with a juvenile ECG pattern whose ECG normalises and d) factors predicting TWI persistence >16 years.
Methods:
Adolescents (mean 15y) in Malta were systematically invited to enrol in a cardiac screening program. Subjects completed a health questionnaire and an ECG at their school. Participants with TWI were labelled as TWI in V1-V2 or extended TWI (V1-V3/4). The latter were followed at 1 year with a repeat ECG. Those with persistent extended anterior TWI were offered evaluation and surveillance.
Results:
The prevalence of isolated anterior TWI was 5.0%, commoner in females (6.3%) independent of athletic ability. Extended TWI was commoner in female athletes (4.2%, non-athletes 2.1%). Females often had shallow TWI without overt ST segment abnormalities. Deep TWI and ST segment changes were more frequent in males. Only 0.2% of cases persisted ≥16 years of age. ST segment characteristics were not able to predict T wave normalisation. No events took place during follow up (40 ± 9 months).
Conclusion:
Anterior TWI is a frequent phenomenon in adolescents, especially in females. Female athletes are also more likely to have extended anterior TWI. Only 0.2% of cases have persistent anterior TWI at 16 years of age. Chest wall anatomy may explain this phenomenon in females. It is uncommon in males, hence why surveillance is more prudent.
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